1. Field of the Invention
The invention relates to an information processing apparatus that includes a receiver configured to receive a packet from a communication line and a processor configured to deactivate its operation in an energy saving mode, and an information processing method for use in the information processing apparatus, and a recording medium having an information processing program stored therein to execute the information processing method in the information processing apparatus.
2. Description of the Related Art
There is a system known in the art in which plural terminal devices are connected to an image processing apparatus such as a printer via a network. In such a system, an image processing apparatus is generally shared by the plural terminal devices, and hence signals are frequently transmitted via the communication line to the image processing apparatus shared by these terminal devices.
In the system having above configuration, if a central processing unit (CPU) of the image processing apparatus receives signals (packet) unnecessary to be processed by the CPU in an energy saving mode, where the CPU of the image processing apparatus is suspending its operation, the CPU is reactivated on receiving the packet. Thus, electric power may be unnecessarily consumed for the unnecessary operation of the CPU.
To prevent such unnecessary electric power consumption, there is proposed a method for controlling a packet to be processed by a CPU to be stored in a memory. In this control method, when an apparatus receives a packet necessary to be processed by the CPU in the energy saving mode, the received packet is temporarily stored in a buffer until the CPU wakes up or resumes its operation, and the stored packet is, after the CPU has awakened or resumed its operation, then stored in the memory.
Japanese Patent Application Publication No. 2009-49699 (hereinafter called “Patent Document 1”) discloses an example of such a control method. The control method disclosed in Patent Document 1 includes determining whether a packet is processable, and updating first and second filters that determine whether to store the packet based on a determined result as to whether the packet is processable. Japanese Patent Application Publication No. 2005-269103 (hereinafter called “Patent Document 2”) discloses another example of the control method. In the control method disclosed in Patent Document 2, a main controller (CPU) of a system controls ON/OFF operation of a function of a network controller in cooperation with the electric power status of the system.
However, with the above examples of the control method, the apparatus in the system needs to have a buffer having a large capacity to temporarily store subsequent portions of the packet completely. However, if the large capacity buffer to temporarily store the packet is provided in the apparatus in the system, the gate array size of the Application Specific Integrated Circuit (ASIC) to control the packets also needs to be increased, which may result in high electric power consumption.